Palin has already expressed her disappointment at the HBO Films TV movie, which will premiere March in the US.

She said: "I think I'll just grit my teeth and bear whatever comes what may with that movie. Well, I am all about job creation and I guess I could provide some of these gals who pretend like they're met with some job security.

"I would ask though that - if they're of the mind of spreading the wealth around - that perhaps they want to spring for one of my kid's braces or something as they capitalise on pretending to be me."

Moore also admitted that she only had a short while to get ready to play Palin.

She confessed: "I basically had two months to prepare, so I cleared my schedule of everything, literally. I cleared everything that didn't involve my family - I just let go of it and spent all my time doing research.

"It was total immersion. The trickiest thing is to take all these physical and vocal characteristics and somehow filter the character's essence through them. And then you personally have to meet them somewhere, too. There's this melding that has to happen."